Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly/openWorld/idempotent/non-destructive, so the safety profile is covered. The description goes further by disclosing what it returns ('slim list of cards'), the absence of a free-text filter, and — most valuably — an explicit do-not-retry rule tied to structuredContent.status with concrete alternatives.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loads purpose and routing, then layers constraints and failure handling. Despite being several sentences, each one carries actionable information (sibling exclusion, filter limits, fallback path) with no filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

No output schema exists, so the description correctly fills that gap by naming the card fields returned, and it covers the failure mode an agent would otherwise mishandle (retrying an 'unavailable' search). For a 14-parameter, read-only search tool this is complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is only 43%, so the description must compensate, and it does for the highest-risk parameter: location 'must be a city or area, not a whole country (ask the user which city).' It also constrains the amenities parameter to the enum-only surface. It adds real meaning beyond the schema, though it leaves the numeric/date parameters (price_min/max, min_beds, max_results) to the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Search Airbnb listings by location and dates') and explicitly distinguishes itself from the sibling trip-based search ('Use when the user is not asking about a specific trip in Tineo'). An agent can route between assistant_airbnb_search_user and assistant_airbnb_search_trip without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit when-to-use and when-NOT-to-use (the Tineo trip case), names the supported filtering surface (amenities enum only, no keyword), and prescribes next steps when status is 'unavailable' (fallback URL, hotel search, support ticket). Nothing about selection is left to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.